دراسة تركيب المجتمع السمكي وبعض الدلائل البيئية في نهر دجلة الدور محافظة صلاح الدين/العراق

Abstract

Water temperature ranges (11 - 27.5) C° and Light transmittance ranges (10 - 127.5 )cm and the values of Dissolved oxygen ranges ( 5.7 - 9.9 )mg / L , water turbidity ranges ( 1.8 - 88.5 )mg / L , pH value ranges ( 7.9 - 8.7) , basicity ranges ( 156.3 - 205.0 )mg / L, hardness ranges ( 106.2 - 375.0 )mg / L chlorides ranges ( 17.5 - 30.0 )mg / L nitrate ranges (0.952 - 1.600 )mg / L total dissolved salts ranges ( 211.5 - 297.5 )mg / L and the suspended materials in water reached ( 21.0 - 27.0 )mg / L. Negative significant correlation was recorded between temperature and each of the total hardness , nitrates , and dissolved salts in water and negative correlation with high significant was recorded between temperature and dissolved oxygen . Twenty three kinds of fish of six families was taken through studying period , seventeen of them were belonged to the Cyprinidae family represented by Acanthobrama marmid fish , Leuciscus vorax , Carassius carassius , Chalcalburnus sellal , Chondrostoma regium , Cyprinion macrostomum , Carassius auratus , Cyprinion kais , Cyprinus carpio, Luciobarbus barbulus , Barbus belayewi , Arbi Barbus grypus , Carasobarbus luteus , Luciobarbus xanthopterus, Garra rufa , Leuciscus cephalus , and Luciobarbus subquincunciatus and one kind of Mugilidae family represented by Chelon aurata fish and two kinds of Bagridae family represented by Mystus pelusius fish and Heteropneustes fossilis and one kind of Siluridae family represented by Silurus triostegus fish and one kind of Cichlidae family represented by Tilapia zillii fish and one kind of Mastacembellidae family represented by Mastacembelus mastacembelus fish . Cyprinion macrostom occupied the maximum value 21.03 % of the total number, as its number reached 122 , then Carasobarbus luteus and Chondrostoma regium rated 16.03 & 15.50 Respectively, and its number 93 & 90. In February, 17 kinds of fish were recorded as the maximum number of fish kinds and 7 kinds of fish were recorded as the minimum number in January related to the two stations. 126 the maximum number of fish were recorded through March rated 21.87% of the total number. 20075.50 gm the maximum weigh of fish was recorded in June rated 20.88% of the total weigh. Between the number of kinds of fish and pH value negative significant correlation was recorded and between the number of fish and pH value negative correlation with high significant was recorded.